Uk Convective General Discussion & Forecasts - April 2012 Part 4

[Staffordshire]

Hey guys, just seen the uksaf forecast and noticed I'm in a risk area, however I'm in a rush ATM, could someone leave a reply telling me what time I'm expected to see somethig if anything and I'll have a look later, much appreciated, and thanks in advance!

[legritter]

just finished my house chores for my mother in law bless her ,just looked at radar and sat pics ,what an adrenaline rush ,if thats how you spell it . i think i will get some sleep in early this evening then get up for about midnight ,lets hope the frogs dont pinch all of our lightning . but on a seriouse note its certainly looking like a seriouse spell of weather to come . but we have all been there before , its when those dry slots aim for your area ,just like the snow one minute a nice big blob then hey presto all gone .certainly looking lively now with some good height on those active clouds ,and some action breaking out ahead .cheers

[Radiating Dendrite]

Well to be honest I expected more for my £3.49

It is a UK radar, not European.

You could always try the french met website.

[Convective]

Just out of curiosity, what kind of air pressure are you looking at in say Houston for example when a storm kicks off?

[Radiating Dendrite]

Just out of curiosity, what kind of air pressure are you looking at in say Houston for example when a storm kicks off?

It is not really related to just air pressure.

There are an enormous amount of variables to consider!

A good place to start is the netweather guides area of the forum.

[staplehurst]

Hey guys, just seen the uksaf forecast and noticed I'm in a risk area, however I'm in a rush ATM, could someone leave a reply telling me what time I'm expected to see somethig if anything and I'll have a look later, much appreciated, and thanks in advance!

I think the models have overdone the shower chance today for inland areas somewhat, 12z soundings offer a 100-200 J/kg CAPE, but it is pretty dry throughout the profiles so it would have to go some to develop any thundery showers today.

GFS has overdone dewpoints by some 2C today (comparing Herstmonceux sounding with GFS forecast), and thus CAPE is likely to have been overdone too in the model fields.

Also concerned at the amount of cloud spilling across NE France/Belgium right now.

[Coast]

London & South East England

Mon 30 Apr

Headline:

Heavy rain overnight and becoming windy.

This Evening and Tonight:

Some bright or clear spells to start this evening but soon becoming overcast and windy as outbreaks of heavy rain spread northwest across the region overnight. Some of the rain could also turn thundery in places. Minimum Temperature 10 °C.

Tuesday:

Windy with rain, heavy and possibly thundery in places with localised flooding possible. Becoming drier and brighter from the south with winds easing but a few heavy showers may develop. Maximum Temperature 16 °C.

Issued at: 1557 on Mon 30 Apr 2012

http://www.metoffice.gov.uk/public/weather/forecast/eastbourne?tab=map&map=SignificantWeather

[Lynxus]

It is a UK radar, not European.

You could always try the french met website.

Click "Euro" on the V4 radar. You can see it in france.

But yeah, Its a UK radar and for the pennies that it is. I think its a good deal!

[Convective]

It is not really related to just air pressure.

There are an enormous amount of variables to consider!

A good place to start is the netweather guides area of the forum.

I know, enormous amounts of everything I was just wondering roughly.

[Coast]

GFS has overdone dewpoints by some 2C today (comparing Herstmonceux sounding with GFS forecast), and thus CAPE is likely to have been overdone too in the model fields.

Almost spat my cappuccino out when I looked at the Weather Online 12z for Herstmonceux!!!! (data error somewhere?)

[Lynxus]

Almost spat my cappuccino out when I looked at the Weather Online 12z for Herstmonceux!!!! (data error somewhere?)

LOLOLOLOOOLOLOLOOOOOOLLLLLLLL

Checkout the cape and LI on that bad boy!

Edited April 30, 2012 by Lynxus

[staplehurst]

Almost spat my cappuccino out when I looked at the Weather Online 12z for Herstmonceux!!!! (data error somewhere?)

Where's that one from? It seems to be assuming the T and T_D are the same for some reason?

The one I'm looking at looks more realistic:

Edited April 30, 2012 by staplehurst

[Coast]

Where's that one from? It seems to be assuming the T and T_D are the same for some reason?

Yep, I saw the dewpoint was an erroneous figure so may have corrupted the other results. You can imagine my face when I first looked at it though!!!!

The chart link I have is from here:

http://expert.weatheronline.co.uk/daten/profi/en/temps/temps.html

[Azores Hi]

What's all this? I go away for a day and come back to find possible French imports! Now I only got 4 hours sleep last night because of a poorly baby, I have a huge amount of driving to do tomorrow and now I have to spend all night watching the bloody radar!

[Harry]

Few sferics in the Channel recently.

MetO warning gone amber for parts of the SW.

Still a depressingly poor level of activity across Benelux at the moment - would have expected something to have fired by now (not suggesting for a minute it wont later)

[Cheshire Freeze]

Couple of showers which have developed over Lincolnshire are now in the vicinity according to the radar. They should be pushing into an area of relatively higher CAPE so we'll see what happens.

[Supacell]

I'm way too far for anything but good luck to you guys and gals down south.

If it had been a higher risk I would have bit the bullet and driven down but its too far for a possibility.

[Joey.G]

Few sferics in the Channel recently.

MetO warning gone amber for parts of the SW.

Still a depressingly poor level of activity across Benelux at the moment - would have expected something to have fired by now (not suggesting for a minute it wont later)

Activity over mainland France has decreased to almost nothing now too, generally the trend accross the channel is not overly promising :/

[Harry]

Activity over mainland France has decreased to almost nothing now too, generally the trend accross the channel is not overly promising :/

Indeed! My thoughts exactly!

[Robbie Garrett]

Hmmm the fact the sky is milky warrants me to beleive something may kick odd. Very off the TAFS don't indicate anything. But let's see, MCS normally kick off in a few hours. I shall be flying in a few hours, may go across Gatwick and have a look at the Channel see what's brewing.

Edited April 30, 2012 by Robbie Garrett

[VillagePlank]

I don't think this one is triggered by surface heating - so mid-afternoon, and early evening formation is not important today (and into tomorrow)

It seems to me that shear and convergence zones are the main triggers, and the lapse rates are sufficient to allow t/storms to develop after initiation over Belgium - it looks like even though the best environment is over Germany there is too much CIN to overcome, so Belgium will advect that moisture as storms develop. The UK will maybe see some as they form and then drift NEE-wards.

Actually, my expected formation zone is a little west of the main forecasts - I'd go for the Fountainebleau region, with showers drifting up to West Sussex, Dorset etc etc with Kent and the far SE missing out with the fun, but not the rain.

Timing? Nothing remotely interesting (for storm lovers) is due to really start even up to 18z,

Certainly a stay up to 3am effort, I'm afraid, I'll probably take a look-see about 00z

Edited April 30, 2012 by Boar Wrinklestorm

[wchris_uk]

clouding over here now, been brilliant sunshine all day! makes a change, hoping for at least one flash,

[Coast]

Certainly a stay up to 3am effort, I'm afraid.

I might get up if I hear it close by, but there's no way I'm staying up until then as I am getting up again 3 hours afterwards!!!

I'm still going with the midnight time slot if anything starts to kick off.

[A.J]

Almost spat my cappuccino out when I looked at the Weather Online 12z for Herstmonceux!!!! (data error somewhere?)

Hehe..lf that came off, we wouldn't be seeing anvils, more like mushroom clouds with fallout and a 100 mile blast radius!

[Costa Del Fal]

I strongly dont expect much tonight. Not much going on in France right now and there is a lot of cloud over France right now. Plenty of Rain for the South though only a bit for here tomorrow.